QUEBEC -- Paul McCartney paid tribute to victims of the Lac-Megantic tragedy Tuesday night, offering free concert tickets and dedicating a song to survivors at a concert.

The pop legend received his longest ovation of the concert on Quebec City's historic Plains of Abraham upon playing "Let It Be."

The song came with a special greeting from McCartney, delivered in French, to the people of Lac-Megantic.

About 1,000 people from the community had been given free tickets to the show, two weeks after a train disaster killed dozens of its residents.

"I would like to dedicate this song to the people of Lac-Megantic," McCartney said in English, before continuing in French and adding, "I dedicate this song to you."

The show began at dusk. As a DJ played a medley of Beatles covers, tens of thousands of people scrambled for spots offering the best vantage points from among the hills of the historic Plains of Abraham battlefield.

Hearing the music was a little more special for Caroline Tremblay than the average rock fan. Her husband was a big admirer of the former Beatle.

Tremblay's husband, Guy Bolduc, was among the dozens killed when fireballs from an exploding train devastated Lac-Megantic's downtown and engulfed the bar where he was performing.

"He adored Mr. McCartney," Tremblay wrote in a moving letter to promoter 3 E Event, Experience, Emotion, which offered free tickets to the musician's show for Lac-Megantic survivors.

"You have allowed my children and me to discover the musical universe of this great artist and (a chance to) bathe in music at a party surrounded by our friends."

The free ticket idea was floated to McCartney's team by the promoter at the beginning of last week. The former Beatle's entourage quickly agreed.

Luci Tremblay, director of communications for promoter 3 E, said organizers were touched by Tremblay's message.

"I was almost crying when I read that message this (Monday) morning," she said. "It was very nice of her to write to us."

Quebec provincial police believe 47 people were killed in the July 6 disaster. About 2,000 people were forced to flee the area, although most have been allowed to return home.

About 70,000 tickets went on sale for the show, which was part of McCartney's "Out There" tour. A spokeswoman for 3 E said tickets were still available about four hours before the gig but she did not want to say how many.

Luci Tremblay said 1,000 tickets had been set aside for Lac-Megantic residents, with about 900 taking up the offer. About 10 buses were also donated in the Lac-Megantic area to bring them to the show.

"We gave them 1,000 tickets but in our mind, if 200 persons want to come, or 400 or 600, the important thing for us was they can do it, no problem," said Tremblay prior to the concert.

She said Mayor Colette Roy-Laroche was pleased with the response because it represents about 10 per cent of the town's population.

Tremblay was also impressed with the interest, given the dire circumstances.

"Some people are preparing funerals, some of them are moving so maybe they're not in the mood to come but what we wanted was those who wanted to come, they can do it."

Those attending were to be seated in the general admission area behind the zone at the front of the stage.

They were not expected to meet with McCartney.

"What we heard is that he's going to talk to them, he's going to say something to them when he's on the stage," Tremblay said, noting that McCartney and his entourage were eager to support the free ticket idea.

In her email to the promoter, Bolduc's wife said people in Lac-Megantic are grateful for the chance to see the singer.

"It's a generous gesture that will give us a little break from the difficult moments," said Caroline Tremblay.

The tickets given to the Lac-Megantic survivors would regularly sell for $99.

The show was McCartney's fourth in the province of Quebec in the last five years.

He packed the Plains in 2008 as part of celebrations to mark the provincial capital's 400th anniversary.

One telecommunications company had even been offering a three-tickets-for-the-price-of-one promotion.

But Tremblay said sales were picking up as the event got closer.

The promoter also collected $65,000 in donations at a Bruno Mars concert on July 8, and set that to the town to help out.

Lac-Megantic residents were the only special guests at the McCartney show.

About 20 seats were also been set aside for blind Quebecers.

With files from Nelson Wyatt in Montreal